Lecture XVI

The recognition of this fact has been particularly obscured in a matter with which we must now briefly deal: in the study of teeth. From the materialistic point of view the teeth are more or less regarded as mere chewing implements. But they are more than that. Their double nature is easily apparent, for if they are tested chemically, they appear to be part of our bone system; but ontogenetically, they emerge from the skin system. The teeth have a double nature and office, but the second of the two is deeply hidden. Compare, for a moment, a set of human teeth with that of an animal. You will find most conspicuous in the latter what I pointed out in the first of our lessons here, the heavy down-draw weight, the massiveness characteristic of the whole skeleton, which I pointed out in the case of the ape. In man, on the other hand, the teeth themselves show in a certain way the effect of the vertical line. This is because our teeth are not only implements for chewing, they are also very essential implements of suction; they have a mechanical external action, and also an extremely fine, spiritualised inward sucking action. We must inquire: what is it that the teeth draw into the body by means of this suction? So long as they are able to do so, they suck in fluorine. Our teeth suck in fluorine. They are instruments of suction for that substance. Man needs fluorine in his organism in very minute amounts, and if deprived of its effects—here I must say something which will perhaps shock you—he becomes too clever. He acquires a degree of cleverness which almost destroys him. The fluorine dosage restores the necessary amount of stupidity, the mental dullness, which we need if we are to be human beings. We require constant dosage with fluorine in very small amounts as a protection against excessive cleverness. The premature decay of the teeth, which is caused by fluorine action, points to excessive demands on the process of fluorine suction. This indicates that man is stimulated to self-defence against dullness through some agency, with which we shall deal presently, although time forbids detailed treatment. Man as it were disintegrates his teeth so that the fluorine action should not go beyond a certain point and make him dull. The interactions of cause and effect are very subtle here. The teeth become defective in order that the individual may not become too stupid! Such is the intimate connection between what is of benefit to man on the one hand, and what tends to cause harm on the other. Under certain circumstances we have need of the action of fluorine, in order not to become too clever. But we can injure ourselves by excess in this respect, and then our organic activity destroys and decays the teeth.